Each 5-gallon bucket is a supercharged worm composting mix ready to go. The base is 3 gallons of worm bedding (high quality worm food) which is made with pure mushroom substrate pre-compost. 1/2 gal of worm castings direct from an active worm composting colony full of live organic living organisms is also added, which is a great kickstart to any new composting bin. To top it off, 1/4 lbs. of red composting worms are added to the mix. These worms are 95% or greater red wiggler with 5% or less of European nightcrawlers for deep aeration and composting.